Joining of metal sheets so that when said joined sheets are viewed from one side,the illusion is created that they form one continuous metal sheet



March 18.- 1969 Filed Oct. 5, 1966 R. S. HOPKINS JOINING 0F METAL SHEETSso THAT WHEN SAID JOINED SHEETS ARE VIEWED FROM ONE SIDE, THE ILLUSIONIS CREATED THAT THEY FORM ONE CONTINUOUS METAL SHEET Sheet of 4 &

RICHARD S. HOPKINS INVENTOR.

ATTORNEY 3,432,909 JOINING OF METAL SHEETS SO THAT WHEN SAID JOINEDSHEETS ARE VIEWED FROM ONE SIDE March 18, 1969 R. s. HOPKINS 1 THEILLUSION IS CREATED THAT THEY FORM ONE CONTINUOUS SHEET Sheet 3 of4Filed Oct. 5, 1966 FIG. 4

S. HOPKINS INVENTOR.

D R A H E R ATTORNEY March 18, 19169 R. s. HOPKINS 3,432,909

JOINING OF METAL SHEETS SO THAT WHEN SAID JOINED SHEETS ARE VIEWED FROMONE SIDE, THE ILLUSION IS CREATED THAT THEY, FORM ONE CONTINUOUS METALSHEET Sheet Filed Oct. 5, 1966 ATTORNEY March 18, 1969 R. s. HOPKINS3,432,909

JOINING OF METAL SHEETS SO THAT WHEN SAID JOINED SHEETS ARE VIEWED FROMONE SIDE, THE ILLUSION IS CREATED THAT THEY FORM ONE CONTINUOUS METALSHEET Filed Oct. 5, 1966 Sheet of 4 FIG. 10

RICHARD S. HOP KINS INVENTOR.

ATTORNEY United States Patent 4 Claims ABSTRACT OF THE DISCLOSURE AV-shaped metal strip with perforation along the apex is joined to afirst metal body along one arm of the V and to a second metal body alongthe other arm. The space between two bodies is filled with a fillermaterial which is then smoothed to give the appearance of continuousmetal body.

The present invention relates to joining of metals and more particularlyto automobile body and fender repair work.

One of the problems in body and fender work is the removal of tornmetal, from a car section, replacing the torn metal with new metalplates and finishing the section so that the mending is invisible. It iswell known that cars with torn parts or visible joints on plates willnot sell so that this type of vehicle has no resale value andfurthermore, is a hindrance to professional people such as actors,doctors, etc. Although, many attempts have been made to provide anarrangement to replace torn portions of automobile sections, none, asfar as I am aware has ever been successful when carried out intopractice commercially.

Thus, an object of the present invention is to provide an arrangementfor joining metals.

Another object of the present invention is to provide an arrangement forjoining metals so as to end up with a nice flush finish which gives theillusion that the joined pieces are in reality a single piece.

Still another object of the present invention is to provide anarrangement for the repair of automobile sections which have torn metal.

Yet another object of the present invention is to provide a method oftreating metal pieces to be joined so as to end up with a flush finish,particularly in joining metal to automobiles in body and fender work.

Generally speaking, the present invention contemplates joining twosheets of metal having corresponding straight edges, wherein one side,i.e., the outer sides of the two joined sheets must present a continuoussmooth painted surface when joined. In other words from the outside,they look like one piece. The sheets to be joined are first inwardlybent to form inner marginal sections along a line parallel to thestraight edge, a short distance there from. A V-shaped strip lengthhaving a plurality of small elongated apertures between two meetingwalls is then placed behind one of these inner marginal sections on oneof the sheets and one of the walls of the strip length is fastened tothe marginal section. A tool is then passed through the elongatedaperture and used to grip the marginal section of the other sheet andthis other marginal section is then fastened to the other wall of thestrip length, forming a V-shaped groove. This groove is then filled witha hardenable plastic which is generally shaped to occupy the groovecontours and extended past the marginal section to the fiat surface ofthe sheets. After the plastic hardens it is sanded down to present3,432,909 Patented Mar. 18, 1969 ice a flush surface with the sheets andfinally painted and baked to finish the job.

The invention as well as other objects and advantages thereof willbecome more apparent from the following description taken in conjunctionwith the accompanying drawing in which:

FIG. 1 represents the rear portion of an automobile in perspective witha torn rear right side plate;

FIG. 2a is a perspective view of one tool which may be used on astraight edge cut in the rear right side plate of the automobile of FIG.1;

FIG. 2b relates to a front perspective view of the tool of FIG. 2a;

FIG.2c shows a section view of the tool shown in FIG. 212, along lines2c2c thereof;

FIG. 3a illustrates in perspective, a portion of a strip length used injoining two sheets of metal;

FIG. 3b presents an end view of the strip length illustrated in FIG. 3a;

FIG. 4 depicts in perspective the use of the tool described in FIGS. 2ato 20 on a sheet of metal;

FIG. 5 shows in perspective the use of the strip length of FIGS. 3a and3b in the joining operation;

FIG. 6 provides a partly schematic explanation of an alternate means offastening the strip length to a sheet of metal;

FIG. 7 is a perspective view of a second tool which may be used in theoperations herein described;

FIG. 8 then explains by a perspective view the use of the tool of FIG. 7in joining a second sheet of metal to the strip length;

FIG. 9a is a perspective view of the now joined sheets of metalworkpiece at an early stage of the finishing operation;

FIG. 9b provides a perspective view of the now joined sheets of metalworkpiece at an intermediate stage of the finishing operation;

FIG. 96 shows the now joined sheets of metal workpiece at the finalstage of the finishing operation; and,

FIG. 10 is a side view corresponding generally to the perspective Viewof FIG. 9a presenting a cross-sectional explanation of the work to beperformed in FIGS. 9b and on the workpiece.

The automobile 12 shown in FIG. 1 has been in some sort of accidentwhich has torn a portion of the right rear side plate sheet 14. In orderto repair this plate 14, the torn edge 16 and part of the plate 18 isout along a straight line 20 so as to form a straight edge 22 (see FIG.5), and another plate sheet 24 must be joined to plate sheet 14. Whenthe work is finished the new plate must form an intimate continuoussection with the rest of the automobile so that even on close inspectionit is impossible to tell that the rear plate consists of two sectionsand not one section. First, the rear plate in the vicinity of the cutedge 22 is carefully sanded down. A marginal section 26 is definedparallel to edge 22 and, the defined marginal section 26 is then bentinwards towards the automobile by means of a power tool 28.

Power tool 28 includes a solid three walled box-like housing 30. The endpiece 32 of this housing has a rectangular wall section 34 and aninwardly inclined wall section 36. A hammer 38 is fitted forreciprocating action between the three walls. This hammer is in generalrectangular shape except for an outwardly inclined plate 40 designed tomate with the inwardly inclined wall section 36. Therefore, when theside plate 14 placed between the end piece 32 and hammer 38 is struck bythe hammer, the sheet will be bent inwardly by the blows of the hammer.Passing out of the housing from the hammer through an opening in thehousing is a piston rod 42 which can be attached to a power source,i.e., a pneumatic power source which can work the hammer.

Using power tool 28 the two marginal sections along the metal sheets tobe joined are inwardly bent. It is now necessary to join the two metalsheets and to accomplish this, a section of strip length 44 is used.

Strip length 44 has a V-shaped cross-section and consists of two walls46 and 48 meeting at an apex 50. Strip length 44 may be made of eithermetal or strong plastic. A key feature of strip length 44 are thekeyhole shaped apertures 52. A plurality of these apertures are disposedalong the length of the apex 50.

To join two sheets of metal using strip length 44, the strip length isfirst fastened to the marginal section 26 of one of the metal sheets byconventional means, e.g., rivets 54. Thus, rivet holes 56 first are madein the metal sheet marginal section and in the strip length, or thestrip length 44 may have ready for-med rivet holes already in the stripwalls. The riveting of the strip wall to the marginal section isaccomplished by means known in the art.

With regard to joining the marginal section to the strip wall, spotWelding may also be employed according to technique described by ArthurL. Phillips Welding Handbook American Welding Society (1962 edition) orby Rupert Le Grand The New American Machinist Handbook--McGraw-Hill BookCo., Inc. 1955, Section 22.

It is now necessary to join the repair sheet or second plate sheet 24 tothe strip length 44. To accomplish this, use is made of a second tool,namely hand angle vise 58. Angle vise 58 includes a handle 60 and ashaft 62 extending from the handle 60. A portion of the outer length ofshaft is threaded 64 and the shaft ends in a locking key 66 which can bea fiat rectangle. Locking key 66 will penetrate keyhole apertures 52 instrip length 44 and when turned 90 will hold the shaft to the striplength. Disposed on the outer length of shaft 62 is a free movingwedge-shaped vice piece 68 which is engaged by a wing nut 70 thre'adedlymounted on the inner end of the shaft threads. In order to fasten therepair plate sheet, i.e., sheet 24 to the strip length 44, locking key66 is first passed through the keyhole aperture 52. The repair platesheet 24 is then placed over the strip length 44. The handle 58 of theangle vise is turned so that the locking key 66 locks the outer end ofthe angle vise in place. The wing nut 70 is turned forcing the apex ofthe triangular vise piece 68 towards the apex of strip length 44 so asto firmly hold the repair plate sheet 24. With the repair plate sheet 24firmly held in place, as shown in FIG. 8, the marginal section of therepair plate sheet 24 is fastened to the strip length either by rivetsor by welding as in the case of the first sheet.

The two plate sheets 14 and 44 are now firmly held together and themarginal sections which form a V- shaped groove. This groove is nowfilled with a hardenable plastic filler material 72 commerciallyavailable which will adhere firmly to the groove. Some of the plasticfiller material is spread out on both sides of the groove. This willprovide an appearance somewhat like that shown in FIGS. 9a and 10. Theplastic filler material is then ground down or sanded down with agrinder or sander until a flat even surface is obtained. The joinedworkpiece is then subjected to a first coating treatment, i.e., a firstcoat of paint 74 as shown in FIG. 9b. After this, the final finishingoperation can be performed using enameling and baking techniques knownin the art. The finished joined workpiece then looks like one sheet ofmetal 76 from the outside.

In carrying the invention into practice, a Spot welding arrangementcommercially sold by Blair Equipment Co. of Flushing, Mich., known asthe Blair Triangle Spot Welder, and described in that companys catalogueof 1963, has been found particularly useful. As a plastic fillermaterial, successful use has been made of such products as Black Magic,Silver Magic, Snowite which are sold by Swiss Laboratory, Inc. ofCleveland, Ohio. A lead or other filler may also be used.

Although the present invention has been described in conjunction withpreferred embodiments, it is to be understood that modifications andvariations may be resorted to Without departing from the spirit andscope of the invention as those skilled in the art will readilyunderstand. Such modifications and variations are considered to bewithin the purview and scope of the invention and appended claims.

I claim: 1. A method of joining two sheets of metal having correspondingstraight edges so that when joined, one side of the two joined sheetspresents a continuous, smooth surface appearance giving the illusionthat the two joined sheets are one continuous sheet, comprising thesteps of: inwardly bending a portion of each sheet along a line parallelto said straight edge thereof so as to define a marginal section;

placing a V-shaped strip length having a plurality of elongatedapertures along the apex thereof behind one of said defined marginalsections;

fastening said strip length to said marginal section;

passing a holding tool through said elongated aperture;

placing the second marginal section over said strip length;

gripping said second marginal section with said tool from behind andfirmly holding said marginal section to said strip length;

fastening said second marginal section to said strip thereby creating aworkpiece of two joined sheets with a groove in between;

filling said workpiece groove with a filler material;

grind polishing said filled groove filler material so as to obtain asmooth surface; and,

paint finishing said joined workpiece so as to present a continuousouter surface.

2. A method of joining metals as claimed in claim 1 wherein fillermaterial is also placed on some of the area surrounding said groove andthe filled groove as well as the surrounding area is treated by grindpolishing.

3. The method of claim 2 wherein said marginal sections are fastened tosaid strip length by welding.

4. The method of claim 2 wherein said marginal sections are fastened tosaid strip length by riveting.

References Cited UNITED STATES PATENTS 2,463,561 3/1949 Riley.

2,946,118 7/ 1960 Steck 29401 2,953,847 9/1960 Reed 29--401 3,066,71912/ 1962 Seznick 2940l 3,091,983 6/1963 Kliss 29-401 JOHN F. CAMPBELL,Primary Examiner.

PAUL M. COHEN, Assistant Examiner.

US. Cl. X-R.

